Electricity generated with water, salt and a three-atoms-thick membrane

July 13, 2016, Ecole Polytechnique Federale de Lausanne
A molybdenum 3-atoms-thick selective membrane. Credit: © Steven Duensing / National Center for Supercomputing Applications, University of Illinois, Urbana-Champaign

Proponents of clean energy will soon have a new source to add to their existing array of solar, wind, and hydropower: osmotic power. Or more specifically, energy generated by a natural phenomenon occurring when fresh water comes into contact with seawater through a membrane.

Researchers at EPFL's Laboratory of Nanoscale Biology have developed an osmotic power generation system that delivers never-before-seen yields. Their innovation lies in a three atoms thick membrane used to separate the two fluids. The results of their research have been published in Nature.

The concept is fairly simple. A semipermeable membrane separates two fluids with different salt concentrations. Salt travel through the membrane until the salt concentrations in the two fluids reach equilibrium. That phenomenon is precisely osmosis.

If the system is used with seawater and fresh water, salt ions in the seawater pass through the membrane into the fresh water until both fluids have the same salt concentration. And since an ion is simply an atom with an electrical charge, the movement of the can be harnessed to generate electricity.

A 3 atoms thick, selective membrane that does the job

EPFL's system consists of two liquid-filled compartments separated by a thin membrane made of molybdenum disulfide. The membrane has a tiny hole, or nanopore, through which seawater ions pass into the until the two fluids' salt concentrations are equal. As the ions pass through the nanopore, their electrons are transferred to an electrode - which is what is used to generate an electric current.

Thanks to its properties the membrane allows positively-charged ions to pass through, while pushing away most of the negatively-charged ones. That creates voltage between the two liquids as one builds up a positive charge and the other a negative charge. This voltage is what causes the current generated by the transfer of ions to flow.

"We had to first fabricate and then investigate the optimal size of the nanopore. If it's too big, can pass through and the resulting voltage would be too low. If it's too small, not enough ions can pass through and the current would be too weak," said Jiandong Feng, lead author of the research.

What sets EPFL's system apart is its membrane. In these types of systems, the current increases with a thinner membrane. And EPFL's membrane is just a few atoms thick. The material it is made of - molybdenum disulfide - is ideal for generating an osmotic current. "This is the first time a two-dimensional material has been used for this type of application," said Aleksandra Radenovic, head of the laboratory of Nanoscale Biology

Powering 50'000 energy-saving light bulbs with 1m2 membrane

The potential of the new system is huge. According to their calculations, a 1m² membrane with 30% of its surface covered by nanopores should be able to produce 1MW of electricity - or enough to power 50,000 standard energy-saving light bulbs. And since (MoS2) is easily found in nature or can be grown by chemical vapor deposition, the system could feasibly be ramped up for large-scale power generation. The major challenge in scaling-up this process is finding out how to make relatively uniform pores.

Until now, researchers have worked on a membrane with a single nanopore, in order to understand precisely what was going on. '' From an engineering perspective, single nanopore system is ideal to further our fundamental understanding of -based processes and provide useful information for industry-level commercialization'', said Jiandong Feng.

The researchers were able to run a nanotransistor from the current generated by a single nanopore and thus demonstrated a self-powered nanosystem. Low-power single-layer MoS2 transistors were fabricated in collaboration with Andreas Kis' team at at EPFL, while molecular dynamics simulations were performed by collaborators at University of Illinois at Urbana-Champaign

Harnessing the potential of estuaries

EPFL's research is part of a growing trend. For the past several years, scientists around the world have been developing systems that leverage osmotic power to create electricity. Pilot projects have sprung up in places such as Norway, the Netherlands, Japan, and the United States to generate energy at estuaries, where rivers flow into the sea. For now, the membranes used in most systems are organic and fragile, and deliver low yields. Some systems use the movement of water, rather than ions, to power turbines that in turn produce electricity.

Once the systems become more robust, osmotic power could play a major role in the generation of renewable energy. While solar panels require adequate sunlight and wind turbines adequate wind, osmotic energy can be produced just about any time of day or night - provided there's an estuary nearby.

Explore further: Revealing ion transport at the nanoscale

More information: Jiandong Feng et al, Single-layer MoS2 nanopores as nanopower generators, Nature (2016). DOI: 10.1038/nature18593

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53 comments

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gculpex
5 / 5 (3) Jul 13, 2016
Is there a shorter route to this?
krundoloss
5 / 5 (6) Jul 13, 2016
That is Awesome! Although I do imagine that producing electricity by making freshwater salty, would only be useful in places with ample freshwater to support the process. It is interesting though, that electricity can be produced simply through osmosis. Great Stuff!
Whydening Gyre
4.8 / 5 (5) Jul 13, 2016
Is there a shorter route to this?

You'd think it was being worked on as we speak. This sounds awesome.
loneislander
3.4 / 5 (5) Jul 13, 2016
I think something is wrong with the numbers here. It says one megawatt per sq meter. That's a LOT! That's bigger than the average power generation station around here. Anyway, here's my dissonance on the matter:

A megawatt is certainly enough energy to desalinate enough water to cover one side of a 1 sq meter membrane - if that's the case, and this thing is located ocean-side, then it can produce an endless supply of fresh water and has an endless supply of salt water too (in fact, this can easily be a closed loop where water is recycled and purified).

Anyway, that's free energy and it violates something about entropy laws - the usual, actually, for this type of announcement. Far too good to be true - this is more power per unit mass than Thorium. As a matter of fact, nothing is consumed at all. A bag of salt, a bucket of water, and some molybdenum disulfide plus a little engineering and this thing could operate in deep space forever. How did this get printed?
loneislander
1 / 5 (3) Jul 13, 2016
Worse: They say this was published in Nature. Ok, so when I learned about osmosis I learned that the liquid with the fewer dissolved ions moved thorough the semi-permeable membrane to fill, and over-fill, the salty water. We used a potato. I've heard nothing in the discussion of osmosis about moving ions to balance the densities. In fact, the thinner liquid always moves through the membrane (in an 'attempt' to dilute the thicker liquid). I've never heard it said anywhere that the stuff dissolved in the liquid moves across - only the liquid itself. This is strange on many levels and I call BS on the entire thing. (is this held over from an April Fools joke?)
Gigel
5 / 5 (4) Jul 13, 2016
That is Awesome! Although I do imagine that producing electricity by making freshwater salty, would only be useful in places with ample freshwater to support the process.

Yes, for example where rivers go into the sea.
Whydening Gyre
3.9 / 5 (7) Jul 13, 2016
That is Awesome! Although I do imagine that producing electricity by making freshwater salty, would only be useful in places with ample freshwater to support the process. It is interesting though, that electricity can be produced simply through osmosis. Great Stuff!

If they could generate juice while desalinating, it'd be a win-win, for sure...
ta2025
4.3 / 5 (6) Jul 13, 2016

Anyway, that's free energy and it violates something about entropy laws - the usual, actually, for this type of announcement. Far too good to be true - this is more power per unit mass than Thorium. As a matter of fact, nothing is consumed at all. A bag of salt, a bucket of water, and some molybdenum disulfide plus a little engineering and this thing could operate in deep space forever. How did this get printed?


I don't see any free energy here. You are doing all sorts of work in extracting ions that nature already provided. There is nothing free about that and nothing is being violated.
BartV
3.7 / 5 (3) Jul 13, 2016
Gigel says:

Yes, for example where rivers go into the sea.


Yes, that is what the article refers to as an estuary.

NeutronicallyRepulsive
5 / 5 (2) Jul 13, 2016
I'm not exactly a chemist. Can someone tell me where the "free" energy is coming from? Or more exactly where is it missing after the process? Can there be some long-term implications for nature? Because it have to come from somewhere. I would not be happy, if it damaged oceans in the long term.
leetennant
5 / 5 (2) Jul 13, 2016
Worse: They say this was published in Nature. Ok, so when I learned about osmosis I learned that the liquid with the fewer dissolved ions moved thorough the semi-permeable membrane to fill, and over-fill, the salty water. We used a potato. I've heard nothing in the discussion of osmosis about moving ions to balance the densities. In fact, the thinner liquid always moves through the membrane (in an 'attempt' to dilute the thicker liquid). I've never heard it said anywhere that the stuff dissolved in the liquid moves across - only the liquid itself. This is strange on many levels and I call BS on the entire thing. (is this held over from an April Fools joke?)


But when I was in Year 9 in 1984....
Whydening Gyre
3.9 / 5 (7) Jul 13, 2016
I'm not exactly a chemist. Can someone tell me where the "free" energy is coming from? Or more exactly where is it missing after the process? Can there be some long-term implications for nature? Because it have to come from somewhere. I would not be happy, if it damaged oceans in the long term.

No free energy. just ion transfer.
I doubt there is insufficient fresh water to pull much of the salt balance out of an ocean. Of course, the now salted fresh water would need to be de-salinated...
But, if their numbers are to be believed, this might provide sufficient power to do that, too...
NeutronicallyRepulsive
5 / 5 (3) Jul 13, 2016
That's why I wrote "free". But ion loses it's energy and its charge is affected. Can this mean something on a larger scale and/or after repeated process? Does it renew it's charge or is it permanent? Can it be depleted (neutralized) and will that affect the environment?
Da Schneib
4.2 / 5 (10) Jul 13, 2016
What's actually happening here is that the solute (the salt ions) is driven through the membrane by osmotic pressure (because the volume of the solvent (water) on the side with the higher salt concentration cannot change, and the solvent moves from the fresh to the salt side, and the osmotic pressure on the salt side can therefore only be reduced by migration of the solute through the membrane to equalize the pressure).

Osmosis is generally demonstrated in terms of the movement of the solvent, but if that is not possible then the solute will attempt to move. The membrane is designed with holes of the right size to permit this, and the electrons from the salt ions are left on the salty side, while the ions move to the fresh side; thus, we have a potential difference between the side with extra electrons and the side with extra ions (and therefore extra holes). By allowing a current to equalize the potential difference, power is generated.

No, this is not bullsh*t.
Da Schneib
4.2 / 5 (10) Jul 13, 2016
As far as it damaging the oceans, if it were going to damage the oceans it would do so far more by merely allowing the rivers to flow unchecked into them. We're merely slowing down the mixing and extracting energy from it; after that's done the waste product is merely salt water. Which is what the oceans are made of already.

This is pretty awesome.
Whydening Gyre
4.2 / 5 (5) Jul 13, 2016

I doubt there is insufficient fresh water to pull much of the salt balance out of an ocean. Of course, the now salted fresh water would need to be de-salinated...

After read DS's description of the process, no de-salinazation necessary...
victor_gallagher
4 / 5 (2) Jul 13, 2016
Hey I have an idea, why don't we use the power generated from this to desalinate sea water ?
antialias_physorg
4.2 / 5 (5) Jul 14, 2016
I think something is wrong with the numbers here. It says one megawatt per sq meter. That's a LOT!

Had the same thought. I wouldn't be surprised if it turns out the writer of this pop-sci article confused MW and mW.

Hey I have an idea, why don't we use the power generated from this to desalinate sea water ?

Since this power is generated by mixing salt and fresh water it would be VASTLY more efficient to just take the fresh water out at that point and pipe it where needed.

Can there be some long-term implications for nature?

Not really. The water still mixes eventually. All you're doing is slowing down the mixing of fresh and salt water. I.e. you're changing the gradient at a river delta a tiny bit. Since this can't really be used accross an entire delta (because: shipping) that effect would be rather small.
ekim
5 / 5 (3) Jul 14, 2016
Rain water would work. A funnel linked to a tube made of this material, submerged in the ocean, could produce power. As the salinity increases in the tube, so does density, causing the salt water to sink in the tube and be released into the ocean out of the bottom of the tube.
PPihkala
5 / 5 (1) Jul 14, 2016
I also think this must be mW (milliWatt) per m2 instead of MW (MegaWatt). Just considering that one system with salt water, fresh water and membrane will be one electrochemical cell, producing low voltage probably under 1 Volt, one must connect a lot of these in series, like in solar panels, where silicon solar cell gives a maximum of 0.7 Volts per cell.

For tropics this capture of rain water and use of it for generation of electrity with controlled release to ocean might not be a bad idea, provided that it is cheaper than other renewables. And with rain water there is bigger salt concentration difference than at estuaries.
bseddon
5 / 5 (1) Jul 14, 2016
This is an interesting discovery but I'm not sure the problems with a production system have been adequately considered - at least in the article.

A 1m x 1m of something 3 atoms thick is not feasible mechanically. A 1mm x 1mm device is not feasible either. So there's no comment about how a device might be manufactured with any geometry that is strong enough while retaining adequate surface area that can be exposed to fluids on either side.

How would such a device report that it's pores are clogged or that the 3 atoms thick barrier has torn. Production systems engineering is more than just basic science though .

jruuttunen
5 / 5 (2) Jul 14, 2016
I also think this must be mW (milliWatt) per m2 instead of MW (MegaWatt).


If it's a mistake, it's not a mistake of this site's author. It's also MW in the university's own news article.
berend
not rated yet Jul 14, 2016
@ekim using rain water, that's a good idea

there's a funny demo on this site: voanews.com/content/estuary-energy/3416728.html
greenonions
4.3 / 5 (6) Jul 14, 2016
It does seem something is very wrong with the power density. Obtaining 1 Mega Watt from a membrane 1 meter square - is the equivalent of a very large wind turbine. Here is the synopsis of the original article - http://www.nature...593.html The table talks abut 10^6 watts per Meter^2. Seems in conflict with this Yale study http://pubs.acs.o...s300060m Showing less than Kwh per Meter^2 at around 90% efficiency. Still a lot of power - and articles use Kwh - vs Watts - which makes it hard to compare.
Da Schneib
4.2 / 5 (5) Jul 14, 2016
I think something is wrong with the numbers here. It says one megawatt per sq meter. That's a LOT!

Had the same thought. I wouldn't be surprised if it turns out the writer of this pop-sci article confused MW and mW.
Says 50,000 low-power light bulbs- divide a megawatt by 50,000 and you get 20W. That's about right for screw-in fluorescent bulbs.

Now, that's not to say that the press release writer at the Ecole Polytechnique Federale de Lausanne wasn't extrapolating something that might not be quite that powerful, but if you like you can find their email address and write them to ask if this is correct: http://actu.epfl....-3-atom/

Bottom of the page under "contacts." Let us know what you find out.
Da Schneib
4.2 / 5 (5) Jul 14, 2016
It does seem something is very wrong with the power density. Obtaining 1 Mega Watt from a membrane 1 meter square - is the equivalent of a very large wind turbine. Here is the synopsis of the original article - http://www.nature...593.html Showing less than Kwh per Meter^2 at around 90% efficiency. Still a lot of power - and articles use Kwh - vs Watts - which makes it hard to compare.
kWh are J, not W. And that article specifies the energy (not power) per m³ of water (not m² of membrane).

We're looking at P = E/t, so 0.75 kWh/m³ implies a flow rate of 1,000,000/750 = 1,333m³/h = 0.37 m³/s. That's about 370 liters/second, or about 100 gallons/second, through a 1 m² membrane.
[contd]
Da Schneib
4.2 / 5 (5) Jul 14, 2016
[contd]
I doubt anyone's going to make a square meter membrane; for process reasons I expect more like a 1 cm² membrane, and there are 10,000 of those in a square meter, so that's around 37 ml/s.

That doesn't seem like a very high rate for a square centimeter of membrane. 37 ml is 2 1/3 tablespoons per second. This sounds reasonable. I'm thinking of a power plant about the size of a standard one, sited on an estuary where fresh and salt water are immediately available, generating a few hundred MW. Waste product is salt water. No heat, since it directly generates electricity.

Somebody who wants to figure out the horsepower of the pumps for the water sources could figure out the efficiency.
Da Schneib
4.2 / 5 (5) Jul 14, 2016
Oh, and you'd filter the water to avoid clogging the membranes. This is obvious.
Da Schneib
4.2 / 5 (5) Jul 14, 2016
Moving right along, it wouldn't interfere with shipping. You've got three pipes: two inlets and an outlet. No big deal.

There're a lot of estuaries around. Like, really a lot.
greenonions
4.3 / 5 (6) Jul 14, 2016
Da Schneib
kWh are J, not W. And that article specifies the energy (not power) per m³ of water (not m² of membrane).
Thanks Da Schneib - you are correct.
It would be fascinating to see a working prototype. You have to have two bodies of water - separated by the membrane. Anode dipped in one side, and cathode in the other. As the water flows past the membrane - a current is generated. Numerous variables - the flow rate, the dimensions of the pipes, the strength of the solution.
antialias_physorg
4.2 / 5 (5) Jul 14, 2016
Rain water would work.

Theoretically. Practically the efficiency of a rainwater system would be very ineffective. It's like making a powerpülant tht harvests lightning strikes: Sure the power in each rain squall/lightning strike is there...but they are far too infrequent in any one location to give you appreciable *average* energy output over time.

...unless you have a huge collection area like, oh, a lake. But in that case you have a river that runs from lake to sea and that IS effectively your rainwater/runoff system (as described in the article).

Moving right along, it wouldn't interfere with shipping. You've got three pipes

Point was: If you use out/in pipes then you're not using 100% of the river. If you want to get 100% of the river through pipes then your shipping will have to go through the pipes (and membranes!), too.
Da Schneib
4.2 / 5 (5) Jul 14, 2016
The whole river?

No, that doesn't sound like a very good idea. There's fish and stuff. The idea is to do it without making a mess.

Nor is it necessary; we're getting a megawatt out of 370 cubic meters per second; that's microscopic compared to the flow rate of even a moderate river. This is scalable; you don't build one big plant, you build a lot of small ones.
Da Schneib
4.2 / 5 (5) Jul 14, 2016
Da Schneib
kWh are J, not W. And that article specifies the energy (not power) per m³ of water (not m² of membrane).
Thanks Da Schneib - you are correct.
It would be fascinating to see a working prototype. You have to have two bodies of water - separated by the membrane. Anode dipped in one side, and cathode in the other. As the water flows past the membrane - a current is generated. Numerous variables - the flow rate, the dimensions of the pipes, the strength of the solution.
I don't think it would work like that. More like, you'd take "spent" water from near the membrane, and pump fresh water and salt water into the two sides far from the membrane at the same rate. And you'd have a bunch of small cells, not one huge tank. But I'm no process engineer; and it depends on the details.
cantdrive85
3.2 / 5 (5) Jul 14, 2016
Drop a hydrophilic tube in a glass of water, shine light, and you have a battery.

http://faculty.wa...science/

antialias_physorg
4.6 / 5 (9) Jul 14, 2016
I went and shot the main author of the article (J. Feng) an email as to the mW/MW issue. Here's the reply (will have to split it to a few posts)


Thanks for the mail and for your questions.
First, I must say this number is an estimation (''estimated power density'' in the paper). Regarding how this is done,

As a standard in this nanofluidic field: the density estimation is done via dividing the obtained power by the cross-section pore area and it has been widely used with single pore systems. For example, 4k W/m2 obtained in the nanotube Nature 2013 paper (ref 5), 7.7 W/m2 obtained in the single channel work ref 22.


[tbc.]
antialias_physorg
4.5 / 5 (8) Jul 14, 2016
In our work:

On a large scale (let's assume the individual pore performance doesn't change), it is convenient to fabricate porous membranes with porosity (25% to 95%, defined as ratio of the total pore volume to the apparent volume ) using electrochemical etching technique, eg in porous silicon. Due to similar fabrication mechanism, we could further assume single layer MoS2 membrane with homogeneous pore size of 10 nm and porosity of 30%, resulting in a pore density of 4x10^15/m2. By exploiting parallelization with such nanoporous membranes, the estimated power density would be 10^6 W/m2 with the KCl salt gradient (1M KCl/1mM KCl, pH11).


[tbc.]
antialias_physorg
4.6 / 5 (9) Jul 14, 2016
The number is high because the area of the nanopore is very small. Compared to the 2013 nanotubes work, due to the thickness difference (0.7 nm vs 1 um), the low resistance of our thin membrane results in higher generated current, and therefore the power density values exceed—by two to three orders of
magnitude—the results obtained with boron nitride nanotubes.

Let me know if you have any questions.

Jiandong Feng


(On a side note: I found the quick reply time awesome :) )
Da Schneib
4.4 / 5 (7) Jul 14, 2016
Good work, @antialias!
humy
not rated yet Jul 15, 2016
from the link:

"..Powering 50'000 energy-saving light bulbs with 1m2 membrane..."

Why "energy-saving" light bulbs in particular? Is this to inflate the figures?

I suspect that was a comment with rather corrupt motive.
I think the link is badly blemished by that comment even though I am sure osmotic power is perfectly feasible and good and the research they have done is good.
The link really could have done without that unfortunate and worse-than unnecessary comment and they really should have left that comment out; bad of them!
Please don't mar good research with a corrupt report on it.
Da Schneib
4.5 / 5 (8) Jul 15, 2016
Why "energy-saving" light bulbs in particular? Is this to inflate the figures?
I suspect the French apply somewhat different standards on these matters and am willing to chalk it up to cultural differences. Remember also that it's a press release, not a scientific paper.
gculpex
5 / 5 (3) Jul 15, 2016
In these types of systems, the current increases with a thinner membrane.


I envisioned a multi-layered system with free flowing free water next to the salt water.
Da Schneib
4.5 / 5 (8) Jul 16, 2016
I envisioned a multi-layered system with free flowing free water next to the salt water.
The salt gets depleted out of the salt water, so actually in a system like this both the fresh and salt water would be free flowing, but your idea still holds.

We need a process engineer. There're probably a couple of tricks we haven't thought of here.
Eikka
3 / 5 (2) Jul 16, 2016
The potential of the new system is huge. According to their calculations, a 1m² membrane with 30% of its surface covered by nanopores should be able to produce 1MW of electricity - or enough to power 50,000 standard energy-saving light bulbs.


That's not a practical proposition anyways, because a 1 sq-m membrane cannot withstand the sheer pressure generated by pulling 1 MW of power out. It will rip unless separated into tiny tiny pieces.

Power is force over distance per second, and the force generated by the flow rate of liquid through such a membrane at 1 million watts per square meter would be enormous - 1 watt is the power to raise an 1 kg mass a meter in the air over 10 seconds - certainly way too much to hold with a membrane just atoms thick.

Da Schneib
4.6 / 5 (10) Jul 16, 2016
@Eikka didn't read the thread.

It doesn't have to be a single one meter square membrane. Ten thousand centimeter square membranes will do just fine.
HeloMenelo
3.9 / 5 (7) Jul 17, 2016
Drop a hydrophilic tube in a glass of water, shine light, and you have a battery.

http://faculty.wa...science/


Unfortunately not even a battery car is going to help to get you aka antigoracle monkey sock to drive
Eikka
2.5 / 5 (4) Jul 17, 2016
Ten thousand centimeter square membranes will do just fine.


And yet the osmotic pressure won't change by making the squares smaller.

A megawatt per square meter is still 100 Watts per square cm, and that's either a lot of water to push through the very thin membrane, or a very high pressure.

The system is generating power from the flow of water much like a water turbine would, only directly. Water comes in and goes out the other end, and the drop in pressure across the device times the flow rate determines power.

100 Watts at a flow speed of 1 m/s means 100 Newtons of force which is equivalent to a 10 kg (22 lbs) weight pressing on the atoms-thick membrane.

You need to split it smaller and smaller still until the membrane can plausibly hold against the pressure, but then your device has several orders of magnitude more support structure than actual membrane, and the whole 1 MW per square meter turns out to be just wishful thinking.

Eikka
2 / 5 (5) Jul 17, 2016
The whole 1 MW/sq-m thing is basically like saying a spoonful of granulated sugar has the surface area of a football field.

Well, try to actually cover a football field with a spoonful of sugar and you get the point.
gkam
1 / 5 (5) Jul 17, 2016
Nothing works where Eikka lives.

I see this being used in the tail end of RO units which have very high concentrations of saline as waste.
TogetherinParis
1 / 5 (1) Jul 18, 2016
Glomerulus.
john_mathon
not rated yet Jul 18, 2016
1MW is an awful lot of ions moving. It is not clear how such a small surface could support current that high and further how are the electrons being stripped from the material in this process?
Whydening Gyre
4 / 5 (4) Jul 19, 2016
A megawatt per square meter is still 100 Watts per square cm, and that's either a lot of water to push through the very thin membrane, or a very high pressure.
The system is generating power from the flow of water much like a water turbine would, only directly. Water comes in and goes out the other end, and the drop in pressure across the device times the flow rate determines power.

I don't think this process works that way at all.
You're not pushing water through it. Salt ions are being pulled thru the nanopores due to a charge differential, nothing else. You just need enough flow along either side of the membrane to keep the salt and freshwater charge differential high enough to keep the ions being pulled thru. Not really a matter of physical pressure.

The MW figure was an extrapolative calculation based on rate of flow through a single nanopore. Doubt it will scale up that well, though.
postfuture
not rated yet Jul 20, 2016
How about we electrocute all living creatures in the ocean with generated by this electricity and then eat all of them?! Is not it a great idea?!!! E.g., we already created a lot of degraded and devastated wetlands, etc., etc. How about more disasters? We just want to save humanity ... and ... always conveniently forget what is great in the lab can potentially lead to catastrophic long term consequences in the natural environment. Our very good intentions ...
Whydening Gyre
3 / 5 (2) Jul 20, 2016
How about we electrocute all living creatures in the ocean with generated by this electricity and then eat all of them?! Is not it a great idea?!!! E.g., we already created a lot of degraded and devastated wetlands, etc., etc. How about more disasters? We just want to save humanity ... and ... always conveniently forget what is great in the lab can potentially lead to catastrophic long term consequences in the natural environment. Our very good intentions ...

Sheesh... You doom and gloom guys sure know how to wreck a party...

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